Inside Health

PERSONAL HEALTH

PERSONAL HEALTH; What Could Be Good About Morning Sickness? Plenty

Published: June 6, 2000

(Page 2 of 2)

But even cooked meat that is not spoiled can be a problem, Dr. Sherman said. If the meat sat around unrefrigerated for a while, it could become contaminated with pathogens like E. coli even though it looks and smells fine, he explained. His evolution-based conclusion: ''A pregnant woman's body responds to the smell and taste of meat because this category of food in general can be dangerous.''

The Cornell biologists do not dispute the role that the hormones of pregnancy are known to play in touching off morning sickness. Rather, Dr. Sherman said, ''the hormones explain how this happens.''

''We're asking why it happens,'' he said. ''Why do the hormones cause these particular symptoms of nausea and vomiting and food aversions? Why not headaches or backaches?'' Their answer is that nausea and vomiting in early pregnancy is protective; it helps to guarantee the next generation will be healthy.

Studies suggest that morning sickness has a genetic component. Women are much more likely to experience it if their mothers or sisters were also susceptible. Forms of morning sickness have also been observed in domestic dogs and captive rhesus monkeys and chimpanzees.

WHAT SHOULD A WOMAN DO? -- Women who do not experience morning sickness should not fret, Dr. Sherman said, if they live in countries where the food supply is safe. But neither should heroic measures be taken to prevent ''normal'' nausea and vomiting. The best way to alleviate the problem is always to have some food in one's stomach. Hence, the common advice to keep crackers on the night table and to eat several before getting out of bed in the morning.

Dr. Sherman said he saw ''no reason to believe that suppressing the symptoms of N.V.P. would improve the outcome of a pregnancy'' unless a woman developed hyperemesis, continual vomiting that occurs in only half of 1 percent of pregnancies and which requires hospital treatment. Ordinary morning sickness, he said, ''is a phenomenon that is adaptive, not pathological. It's not a symptom of a failing female body. It's a temporary condition that occurs early in pregnancy when fetal demands are small and would not be a major drain on a woman's resources.''

Dr. Sherman also sees no reason to force a pregnant woman to consume any foods to which she has developed an aversion. In most women, aversions that start in the first trimester dissipate during the second along with a waning of nausea.

Of course, all pregnant women should be taking daily prenatal vitamin-mineral supplements, which help compensate for any nutrients missing while suffering from N.V.P. Most important in the first months of pregnancy is folic acid (or folate), which has been shown to greatly reduce the risk that the baby will suffer a spinal defect when consumed at a level of 400 micrograms a day. Since January 1998, flour and grain products (foods that are unlikely to be on a pregnant woman's list of aversions) have been fortified with folic acid.

Drawing (Sara Schwartz) Chart: ''A Built-In Survival Mechanism: Morning Sickness'' Authors of a new study describe the symptoms of morning sickness, nausea and vomiting, as a wellness insurance that protects the mother and her unborn child. MORNING SICKNESS AND THE RISK OF MISCARRIAGE -- The authors cite several previous studies to show the correlation between morning sickness symptoms and infrequent miscarriages (fetal death before 20th week). The authors cite several previous studies to show the correlation between morning sickness symptoms and infrequent miscarriages (fetal death before 20th week). OR STILLBIRTHS -- Morning sickness symptoms and fetal deaths, including stillbirth (fetal death after 20th week) The researchers also gathered evidence that meat, eggs, fish and poultry are the foods likeliest to harbor infectious and toxic organisms, and that women experiencing morning sickness frequently have an aversion toward those foods. SPECIFIC FOODS PRESENT GREATER DANGER -- The researchers also gathered evidence that meat, eggs, fish and poultry are the foods likeliest to harbor infectious and toxic organisms, and that women experiencing morning sickness frequently have an aversion toward those foods. Charts showing miscarriages and stillbirths, and average number of aversions or cravings.